International courts and tribunals are firstly and particularly conceived to settle legal disputes between States and/or other organs or individuals admitted as parties according to the statute of the respective court by means of a binding decision. An advisory function is not inherent in the function of a judicial body, but has to be transferred expressly upon a court or tribunal in the constituent instrument. For non-standing judicial bodies, i.e., arbitral tribunals, an advisory function is rather unusual, but not altogether ruled out: The parties to a compromis may empower the tribunal to give an advisory opinion.